1. Field of Invention
The present invention relates to a frying oil or fat composition for use to fry therein foodstuffs such as meats, fishes, shellfishes, and vegetables. Particularly, the invention relates to a frying oil or fat composition which is suitably employed to prepare a deeply fried foodstuffs having favorable appearance, taste and crisp.
2. Description of Prior Art
The frying oil or fat composition (hereinafter, simply referred to as "flying oil composition" or "frying oil") is employed as heating medium for cooking foodstuffs on frying pans, frying pots, cooking plates, or the like, and also for keeping the cooked foodstuffs from the frying pans and the like. Further, the frying oil or fat composition is used to impart to the cooked foodstuffs favorable taste and crisp. For example, the so called "Tempura" (Japanese deep-fat fried fish) and other fried foodstuffs are cooked using a liquid oil or a fat such as corn oil, soybean oil, rapeseed oil, cottonseed oil, rice bran oil, safflower oil, high-oleic safflower oil, sunflower oil, high-oleic sunflower oil, sesame oil, olive oil, palm oil, or lard, singly or in combination of one or more of these oils or fats. It is known that fried foodstuffs such as Tempura having favorable appearance, taste and crisp are not easily produced without trained skill. For instance, highly trained skill is required to appropriately choose the oil or fat, mixing ratio of oils and fats, frying temperature and frying period. Further, high skill is required to deal with the foodstuffs in the frying oils. The fried foodstuffs produced by those having poor skill give poor appearance (for example, lack of flowery coating, particularly for Tempura), mal odor or smell due to oxidation of the employed oil by heating under inappropriate conditions, unfavorably oily taste and poor crisp.
Heretofore, the following procedures have been generally adopted for obtaining favorably fried foodstuffs:
(1) In order to obviate excessively oily taste, the content of gluten in the wheat flour to be employed for coating the foodstuffs is reduced; flour concentration in the aqueous flour mixture (dough) for the preparation of the coating is reduced; and the aqueous flour mixture is produced using chilled water to suppress production of gluten in the flour;
(2) In order to impart to the fried foodstuffs favorable crisp, the foodstuffs are continuously moved or swayed in the frying oil to extend the oil uniformly within the coating; and the frying procedure is performed in a frying oil at a higher temperature so as to quickly evaporate a great amount of water from the coating; and
(3) In order to reduce oxidation or deterioration of the frying oil as well as to obviate excessively oily taste, an anti-oxidant is incorporated into the frying oils. Unfavorable effects given by oxidation of oils are reported in J. Nutrition, 90, 199 (1960) and other publications. As antioxidants, BHA and TBA are employed. Further, a silicone oil is added to the frying oil to keep the oil from atmospheric oxygen. Recently, antioxidants of natural origin such as lecithin, tocopherol and extracts of coffee and tea are used.
The frying oil or fat preferably is in the form of liquid at room temperature. Japanese Patent Provisional Publications No. 47(1972)-34,703, No. 63(1988)-79,560 and No. 63(1988)-63,343 describe that nonionic surface active agents of polyalcohol type having a high esterification percentage (namely, having esterification percentage of not less than 80%, and low HLB) which are able to keep the oil from formation of crystalline structure therein, or that an oil portion which easily crystallizes at low temperatures is removed by means of wintering.